Small Aperture Antenna Arrays for Direction of Arrival Estimation

Area of Science:

• Electromagnetics and Signal Processing
• Antenna Array Design
• Direction of Arrival Estimation

Background:

• Direction of Arrival (DOA) estimation performance is linked to the spatial covariance matrix.
• The Cramer-Rao Bound for DOA estimation is also closely related to this matrix.
• Small aperture antenna arrays are defined as having few elements with interelement spacing <= 0.5 wavelength.

Purpose of the Study:

• Establish design criteria for small aperture antenna arrays for improved DOA estimation.
• Investigate the impact of element spacing and element dissimilarity on DOA performance.
• Determine the role of mutual coupling in DOA estimation for small aperture arrays.

Main Methods:

• Derivation of design criteria using the spatial covariance matrix.
• Analysis of the relationship between matrix information and DOA estimation performance.
• Demonstration of design principles through theoretical analysis and simulation.

Main Results:

• Optimal small aperture antenna arrays should feature non-uniformly spaced elements.
• Dissimilar antenna elements are crucial for enhancing DOA estimation accuracy.
• Mutual coupling, when incorporated into the estimation process, improves DOA performance.

Conclusions:

• Non-uniform spacing and dissimilar elements are key design criteria for small aperture DOA arrays.
• Mutual coupling should be leveraged, not eliminated, to boost DOA estimation performance.
• The findings provide a new framework for designing high-performance small aperture antenna arrays.